Average DDoS attack sizes decrease 85% due to FBI’s shutdown of DDoS-for-hire websites

The FBI’s shutdown of the 15 largest distributed denial-of-service (DDoS) for hire vendors (booters) reduced the overall number of attacks worldwide by nearly 11 percent compared to the same period last year.

Along with the fewer total attacks, the average size decreased by 85 percent as did the maximum attack size by 24 percent, indicating the FBI crackdown was effective in reducing the global impact of DDoS attacks.

However, booter websites are poised to make a comeback despite the crackdown due to growing botnets and incessant demand for DDoS-for-hire services, according to the Nexusguard Q4 2018 Threat Report.

The quarterly report, which measures thousands of DDoS attacks around the world, showed that DDoS-for-hire websites represent the legal loopholes from website and network ownership, as well as IoT devices and rapidly changing infrastructure that allows hackers to exploit vulnerabilities before owners or manufacturers can thwart them.

These booters were alleged to have been responsible for generating more than 200,000 DDoS attacks since 2014. Despite the effective crackdown by federal law enforcement on these sites in December 2018, Nexusguard researchers warns that organizations should remain vigilant as other booter services may rise to take their place and attack volume will revive.

“Seizing command-and-control servers, booters and other resources has been a big part of the FBI’s fight against cybercrime, but this shutdown only scratches the surface of a global problem,” said Juniman Kasman, chief technology officer for Nexusguard.

“While booters are visible targets, businesses must also manage the vulnerabilities that stem from unpatched hardware and software, human error and new attack methods, especially as the footprint of IoT expands.”

More than 90 percent of DDoS attacks rated smaller than one Gbps in size. “Bit-and-piece” attacks continued from last quarter into Q4, employed in many campaigns regardless of the vector utilized.

Bit-and-piece attacks beat detection thresholds in that the targeted IP address receives only a small number of responses in each organized campaign, leaving little or no trace. Black-holing all traffic to an entire IP prefix is a costly approach, due to the tactic blocking access to various legitimate services.

Other report findings show:

• HTTPS attacks ranked third highest in attack popularity, compared to user datagram protocol (UDP) and simple service discovery protocol (SSDP) attacks. An unusual pattern of frequently repeated HTTPS attacks was observed against one customer, occurring nearly every day in December and up to 13 times in one day, demonstrating the attacker’s commitment to disrupting the target’s network for all of December, the busiest time of year for retail and entertainment businesses
• Attack durations increased more than 175 percent to more than 450 minutes on average compared to last year. Attacks in the quarter were routinely targeted to occur during peak service hours for maximum disruption.
• China held its lead as source of DDoS attacks, with 23 percent of attacks originating in the country and 18 percent originating in the United States.